As soon as I saw the trailer for sad-looking cute dog movie A Dog's Purpose, I knew with 100 percent certainty that it was going to be a sentimental tear jerker created with the express intention of making people cry. I also knew that I would 100 percent be on board to see it, despite the knowledge that it would make me sob in front of strangers. But why? Why would I want to subject myself to such sadness, embarrassment, and the painful memories of losing my childhood dog? Well, as it turns out, it's possible that seeing sad movies can actually make us feel better.

As Aristotle theorized, “Tragic plays have the capacity to purify the spirit and aid us in coping with aspects of life that cannot be reconciled by rational thought.” With movies being the new plays (sorry Aristotle), it's possible that this holds true today. Sad movies are just as popular as any other film; earlier this year, the weepy drama Me Before You earned $56 million, a significant success. And over this past holiday season, family trauma indie Manchester by the Sea has made an impressive $34 million and collected a number of awards nominations and wins. With Michelle Williams crying her way through the film's trailer, you'd think people might be turned off by the prospect of seeing such a sad movie, but that doesn't appear to be the case.

Roadside Attractions

So why do we do it? Why do we expose ourselves to such harrowing, depressing, and sob-inducing films? Well, as The Guardian reports, researchers at Oxford University theorize that watching sad movies boosts emotions of group bonding, increases pain tolerance, and causes pain-killing, feel-good, empathy-increasing Oxytocin in the brain to spike. “The argument here is that actually, maybe the emotional wringing you get from tragedy triggers the endorphin system,” said Robin Dunbar, a co-author of the study and professor of evolutionary psychology at the University of Oxford. Crying together triggers the same chemical response as laughing together, dancing together, or working as a team.

But there may also be another reason why we feel better after watching a traumatic film: pure selfishness. As The Atlantic writes, basing its conclusion on research done by Ohio State, "This crying thing has nothing to do with catharsis. Seeing others in pain reminds us of how good we have it, finds research. 'People seem to use tragedies as a way to reflect on the important relationships in their own life, to count their blessings,' said researcher Silvia Knobloch-Westerwick."

Warner Bros.

So having a good sob at the end of Me Before You or at just the trailer for A Dog's Purpose might give you and I a few things: a boost of Oxytocin to increase our empathy, a bonding experience with others, and a moment to reflect on how lucky we are that we're not the ones experiencing the same thing the movie's characters are (even if we have before). And hey, maybe sometimes we just like it. Everyone knows that feeling you get after a good cry; how it can bring you huge relief and provide you new perspective. Maybe it's what Aristotle was talking about; watching sad entertainment is a way of helping us understand that which is hard. The fact that it's the result of all of the science going on in our brains doesn't make it any less meaningful.

So sometime shortly after Jan. 27, when A Dog's Purpose opens, you'll probably catch me at the movie theater with a giant popcorn, frosty drink and a big box of tissues, because my childhood dog passed away about 10 years ago, and I don't really mind having a good, heaving cry to remember him.